JP2015529118A - Actuator control in a breast pump system - Google Patents

Abstract

The present application relates to a breast pump system including a pump unit, an actuator that drives the pump unit, and a power source that powers the actuator, and a method for use in such a system. When the pump unit is turned on, the actuator is driven at a first speed, and after the load on the actuator reaches a predetermined level, the actuator continues to drive the actuator at a second speed that is faster than the first speed. A speed regulation module is provided.

Description

  The present application relates to a breast pump. More specifically, the present application relates to actuator control in a breast pump system where, when turned on, a low voltage is initially applied to the actuator and a high voltage is applied after a predetermined period of time.

  A breast pump is used to express milk at a convenient time for the mother to be stored for later consumption by the child. A breast pump operates by creating a vacuum to mimic a child's ingestion behavior. Conventional breast pumps are categorized as mechanical or electrical, where the user manually operates the vacuum pump to generate the necessary vacuum, and in the electrical type, the vacuum pump is driven by an electric motor. Electric breast pumps generally reduce system power consumption, improve system reliability to avoid potential damage to the user, and noise associated with breast pump operation. It is desirable to lower the level. High noise levels prevent the mother from relaxing and also affect the lactation reflex necessary to ensure milking.

  The present invention has been made in this context.

  US Patent Application Publication No. 2008 / 009815Al discloses a closed loop vacuum control system for an electric breast pump. The vacuum control system includes a vacuum source that provides a vacuum to the milk collection kit. The vacuum control system also includes a device that sets the vacuum level generated by the vacuum source to a preselected vacuum level. The vacuum control system further includes a sensor that senses the actual vacuum level generated by the vacuum source during operation. The controller continuously compares the preselected vacuum level with the actual vacuum level. A proportional valve is also provided that adjusts the actual vacuum level to correspond to a preselected vacuum level. In this way, the proportional valve can adjust the actual vacuum level in response to a signal from the controller.

  The present invention seeks to provide a breast pump system and method that substantially alleviates or solves one or more of the above problems.

  According to the present invention, when the pump unit, the actuator that drives the pump unit, the power source that supplies power to the actuator, and the vacuum pump are turned on, the electric motor is driven at the first speed, and the load on the motor is reduced. After reaching the predetermined level, a breast pump system is provided that includes an actuator speed adjustment module that continues to drive the electric motor at a second speed greater than the first speed. This can prevent the motor from operating at high speed and generating excessive noise when the motor is first turned on and the load is low.

  The actuator may be an electric motor such as a direct current (DC) electric motor.

  The power supply uses pulse width modulation (PWM) to power the actuator, supplies a first voltage by powering at a first duty cycle, and a second duty cycle that is higher than the first duty cycle. To supply the second voltage. This allows actuator control to be applied to existing PWM designs without the need for additional hardware.

  The power supply gradually increases the first voltage to the second voltage during a predetermined period. The actuator resistance increases gradually as the rotational speed increases, and increasing the first voltage to the second voltage during the period provides smooth acceleration of the actuator during the period Can do.

  The breast pump system further detects an input current supplied to the actuator, and in response to the detected input current exceeding a threshold current level indicative of a threshold vacuum level in the breast pump, a power supply that reduces the speed of the actuator. Includes control module. This can prevent the pump from continuing to operate in situations where there is already a high vacuum in the breast pump and further use of the pump will further increase the vacuum.

  The power control module suspends power supply to the actuator in order to reduce the speed of the actuator. In this way, the pump unit can be turned off as soon as the threshold current is exceeded, preventing further increase of the vacuum.

  The pump unit further includes a vacuum pump and a valve that releases the vacuum generated by the vacuum pump, and in response to the detected input voltage exceeding a threshold current level, the power control module further includes Indicates a failure. This has the advantage that a valve failure can be detected, so that appropriate action can be taken, for example by telling the user that the valve should be repaired or replaced.

  The power supply uses pulse width modulation (PWM) to power the actuator according to the duty cycle, and the power control module suspends power supply to the actuator by setting the PWM duty cycle to substantially zero. . With this approach, the actuator cutoff function can be performed by the PWM controller, so no additional hardware is needed to isolate the actuator.

  The breast pump system further drives the actuator at a first speed when the pump unit is turned on, and after the load on the actuator reaches a predetermined level, the actuator is moved to a second speed higher than the first speed. An actuator speed adjustment module that continues to drive at a speed of This can prevent the actuator from operating at high speed and generating excessive noise when the actuator is first turned on and the load is low.

  The second predetermined period is the time taken for the pressure difference generated by the pump unit to reach a predetermined level. The predetermined level is selected as a level at which the pump speed can be adjusted so that the back pressure of the operation relative to the pressure differential maintains the noise within an acceptable level.

  The breast pump system further includes a breast pump having a chamber and a membrane receivable in the chamber to divide the chamber into a first space and a second space, the membrane being depressurized in the second space. The surface of the chamber that is deformable in the chamber in response to the reduced pressure in the first space and that can contact the membrane and / or the surface of the membrane that can contact the chamber is such that the membrane is in contact with the chamber. It has a textured surface finish so that the noise level that occurs when contacting, moving along the chamber, or moving away from the chamber is minimized. This acts to reduce the level of noise caused by moving the flexible membrane surface in contact with the chamber surface, moving along the chamber surface, or moving away from the chamber surface. To do. The textured surface finish serves to reduce the surface area at which the membrane and chamber contact each other.

  In one embodiment, the surface of the chamber that can contact the membrane has a textured surface finish. In this configuration, the textured surface is easily formed by the rigidity of the shell that forms the chamber.

  In another embodiment, the surface of the membrane that can contact the chamber has a textured surface finish.

  The chamber includes a sidewall on which the membrane is placed before and / or during deformation, and the surface having a textured surface finish is formed by the sidewall and / or a portion of the membrane that can contact the sidewall Is done. Thus, the surface area of the membrane surface that extends around the membrane and contacts the circumferential surface of the side wall against which the membrane is biased is minimized.

  The surface may have a textured surface finish having an arithmetic average roughness (Ra) of about Ra 1.6 μm.

  The surface may have a textured surface finish having an arithmetic average roughness (Ra) greater than Ra 0.8 μm. One advantage of this configuration is that having a textured surface finish greater than Ra 0.8 μm reduces noise caused by the movement of the membrane surface over the surface of the chamber.

  The surface may have a textured surface finish having an arithmetic average roughness (Ra) of less than Ra 3.2 μm. One advantage of this configuration is that having a textured surface finish of less than Ra 3.2 μm limits excessive wear of the membrane as it moves over the surface of the chamber.

  In yet another embodiment, both the surface of the chamber that can contact the membrane and the surface of the membrane that can contact the chamber may have a textured surface finish.

  In such an embodiment, the chamber surface and the membrane surface each have a textured surface finish with an arithmetic average roughness (Ra) greater than Ra 0.4 μm. One advantage of this configuration is that each surface having a textured surface finish eliminates noise caused by moving the membrane surface over the surface of the chamber, contacting the surface of the chamber, or leaving the surface of the chamber. The surface is the point that minimizes the arithmetic average roughness (Ra) required to minimize.

  According to another aspect of the present invention, a chamber and a membrane receivable within the chamber so as to divide the chamber into a first space and a second space, the membrane being depressurized in the second space. The surface of the chamber that is deformable in the chamber in response to the reduced pressure in the first space and that can contact the membrane and / or the surface of the membrane that can contact the chamber is such that the membrane is in contact with the chamber. A breast pump is provided having a textured surface finish so that the noise level that occurs when contacting, moving along the chamber, or moving away from the chamber is minimized.

  In accordance with the present invention, there is also provided a method for use in a breast pump system that includes a vacuum pump, a direct current (DC) electric motor that drives the vacuum pump, and a power source that powers the electric motor. The method includes driving an electric motor at a first speed when the vacuum pump is turned on, and after a second predetermined period after the motor is turned on, And continuing to drive at a second speed higher than the speed.

  The method further includes detecting an input current supplied to the electric motor and, in response to the detected input current exceeding a threshold current level indicative of a threshold vacuum level in the breast pump, to reduce the speed of the electric motor. Reducing.

  The method further includes supplying power by supplying a first voltage to the electric motor when the vacuum pump is turned on, and after a predetermined period of time after the motor is turned on, Providing a second voltage that is higher than the first voltage.

  According to the present invention, a vacuum pump, a direct current (DC) electric motor that drives the vacuum pump, a power source that supplies power to the electric motor, and an input current supplied to the electric motor are detected, and the detected input current is milked. There is further provided a breast pump system including a power control module that reduces the speed of the electric motor in response to exceeding a threshold current level indicative of a threshold vacuum level in the machine. This avoids the pump continuing to operate in situations where there is already a high vacuum in the breast pump and further use of the pump will increase the vacuum to a level that can cause discomfort or damage to the user. be able to.

  According to the present invention, when the pump unit is turned on, the first voltage is supplied to the actuator when the vacuum pump, the direct current (DC) electric motor that drives the vacuum pump, the power source that supplies electric power to the electric motor, A breast pump system is further provided that includes a power control module that provides the actuator with a second voltage that is higher than the first voltage after a predetermined period of time after the actuator is turned on. By starting the actuator using a low voltage, a high inrush current is avoided and the power consumption of the actuator is also reduced.

  These and other aspects of the invention will be apparent with reference to the embodiments described below.

  Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings.

FIG. 1 shows a breast pump system. FIG. 2 shows the operating unit of the breast pump system of FIG. FIG. 3 shows a direct current electric motor for use in a breast pump system. FIG. 4 shows a breast pump system using pulse width modulation control. FIG. 5 shows the steps of the method of supplying power to the electric motor in the breast pump system. FIG. 6 shows a breast pump system. FIG. 7 shows a graph displaying the motor current profile over time in the breast pump system of FIG. FIG. 8 shows method steps for use in a breast pump system such as the breast pump system shown in FIG. FIG. 9 shows the steps of the method for use in a breast pump system such as the breast pump system shown in FIG. FIG. 10 shows a cross-sectional view of the breast pump shown in FIG.

  With reference to FIGS. 1 and 2, a breast pump system is shown. As shown in FIG. 1, the breast pump system 100 includes a breast pump 110, also known as a milking unit, and an operating unit 120 connected to the breast pump 110 by a tube 130. Tube 130 provides a fluid connection between breast pump 110 and operating unit 120. The tube 130 may be used to provide an electrical connection between the breast pump 110 and the operating unit 120. For example, the tube supplies an operating signal or power between the breast pump and the operating unit. In this configuration, the operation unit 120 is separated from the breast pump 110, but the operation unit may be formed integrally with the breast pump 110, as a matter of course.

  The milking machine 110 has a main body 111, a funnel 112, a collection tank 113, and a diaphragm 114 coupled to the vacuum line 130. The collection tank 113 or collection container collects milk squeezed from the user's breast and may take the form of a baby bottle or bag. The collection tank 113 is attached to the main body 111 by a threaded joint, but it will be appreciated that other removable attachment means such as clips (not shown) may be used. Breast receiving funnel 112 is configured to receive a user's breast and has a mouth and a throat. The mouth is open at the outer end of the funnel 112, and the funnel 112 converges from the outer end toward the throat, forming a hollow recess in which the breast is received. The main body 111 fluidly connects the funnel 112 to the collection tank 113. A fluid passage through the body 111 is formed from the breast receiving space of the funnel 112 to the collection tank 113. The main body 111 is formed from an outer shell. The main body 111 is formed integrally with the funnel 112, but the funnel 112 may of course be detachable.

  The operating unit 120 includes a pump unit and an electric motor that drives the pump unit (these are not shown in FIG. 1). The electric motor functions as an actuator. The pump unit creates and releases a vacuum in the vacuum path. The means for generating the reduced pressure and the means for releasing the reduced pressure are separate components. In particular, in this embodiment, the vacuum unit includes a vacuum pump (not shown in FIG. 1) and a pressure release valve (not shown in FIG. 1). The vacuum pump functions as a decompression unit. The pressure release valve functions as a means for releasing the reduced pressure. The vacuum pump is fluidly connected to the main body 111 via the tube 130. The release valve opens periodically to release the reduced pressure generated by the vacuum pump. This creates a periodic pressure difference. Of course, however, different vacuum generation systems may be used. For example, naturally, the means for generating the reduced pressure and the means for releasing the reduced pressure may be integrally formed.

  A chamber is formed in the body 111 of the breast pump 110. The chamber is formed along the fluid passage and has a vacuum port. Since the vacuum port leads to tube 130, the vacuum pump can provide a vacuum in the chamber.

  In this embodiment, the membrane is received in the chamber. Membranes, also known as diaphragms, are flexible. The membrane divides the chamber into a first space and a second space. The first space is in fluid communication with the vacuum port. Accordingly, a reduced pressure is generated by the vacuum pump in the first space. The second space is in fluid communication with a fluid passage between the breast receiving space of the funnel 12 and the collection tank 113. Thus, the second space is in direct fluid communication with the breast received in the funnel. A one-way valve is disposed between the chamber and the collection tank 113. When a reduced pressure is generated in the first space, the membrane deforms and is drawn in the direction of the first space. Thus, the deformation of the membrane creates a reduced pressure in the second space of the chamber. When the breast is received in the mouth of the funnel, a vacuum is formed in the funnel. The reduced pressure acts on the user's breast and milk is squeezed out of the breast.

  The above configuration indirectly creates a vacuum in the user's breast. Of course, it is also possible to create a vacuum in the user's breast by omitting the membrane so that a direct fluid connection is formed between the vacuum pump and the funnel. Furthermore, in this embodiment, separate breast pumps and operating units are provided, but in other embodiments the components of the breast pump system, such as collectors, funnels, vacuum pumps, electric motors and power supplies, It may be accommodated in a single body. For example, the components of the operating unit may be incorporated into the body of the breast pump, in which case no separate operating unit is required.

  FIG. 2 shows the operation unit 120 in more detail, a vacuum pump 221 that generates a vacuum, a direct current (DC) electric motor 222 that drives the vacuum pump 221, a power source 223 that supplies power to the electric motor 222, and a power source And a power control module 224 for controlling the H.223. The power supply control module 224 supplies a first voltage to the electric motor 222 when the vacuum pump is turned on, and after a predetermined period from when the electric motor 222 is turned on, The power source 223 is controlled to supply a second voltage higher than the voltage. This can avoid high inrush currents when the electric motor 222 is initially turned on and the motor resistance is low, as will be described below with reference to FIG.

  The present embodiment relates to a breast pump system including an electric motor with a DC brush. However, it will be appreciated that the present invention is applicable to breast pump systems that include other types of motors. In other configurations including, for example, another type of motor or a DC brushed electric motor, the voltage drop may be caused by slack lines or different faults.

  FIG. 3 shows a DC electric motor 322 for use in a breast pump system, such as the breast pump system as shown in FIGS. The electric motor 322 includes a coil 301 of wire that is wound around an armature that is omitted in FIG. 3 for the sake of clarity. Permanent magnets 302 and 303 are positioned on both sides of the coil 301, and the coil 301 is connected to a power source via a commutator segment 304 and a carbon brush 305. Therefore, the motor 322 is called an electric motor with a DC brush. However, the present invention is not limited to use in conjunction with a DC brushed motor. In other embodiments, other types of DC motors may be used, for example brushless motors. Those skilled in the art will be familiar with the operating principle of an electric motor with a DC brush, and therefore a detailed description is omitted here to maintain brevity. Although two commutator segments 304 are shown in FIG. 3, in general, any number of segments greater than two may be provided.

  As the armature rotates, the current flowing through the coil 301 produces a back electromotive force (EMF) field opposite to the armature and the rotation of the coil 301. This back EMF field increases resistance when the motor 322 is spinning at high speed. However, when the motor 322 is first turned on, there is no back EMF field and only resistance is provided by the coil 301 itself, but this resistance is negligible. However, this leads to a current spike when the motor is first turned on. In an embodiment of the present invention, when the motor is first turned on, the power supply provides a low voltage to increase the low voltage to a higher voltage as the motor speed increases and the resistance increases. Be controlled. The supply voltage may be increased after a predetermined period. This predetermined period may be the time it takes for the motor to reach the required operating speed. This approach can avoid the first current spike, called inrush current, and thus reduce the total power consumption of the motor in use. In addition, damage due to inrush current due to, for example, spark between commutator segment 304 and brush 305 is avoided, carbon brush wear is reduced, and the operating life of motor 322 is extended.

  Referring next to FIG. 4, a breast pump system using pulse width modulation control according to one embodiment of the present invention is shown. In this embodiment, the operating unit 420 is provided for use in a breast pump system such as the breast pump system shown in FIG. The operation unit 420 is the same as the operation unit of FIG. 2, and includes a vacuum pump 421, a DC electric motor 422, a power supply, and a power supply control module 424. Of course, in other embodiments, rather than providing a physically separate operating unit and collection unit, the components of the operating unit 420 and the collection unit may be incorporated into the breast pump body.

  More specifically, in the present embodiment, the power supply powers the electric motor 422 using pulse width modulation (PWM). The power source includes a power source 423-1 and a field effect transistor (FET) 423-2. However, in other embodiments, different types of switches other than FETs may be used to switch PWM control power on and off. The power supply control module 424 is a PWM control module that controls the switch 423-2 used for PWM control. The PWM control module 424 controls the PWM switch 423-2 with a first duty cycle, so that when the motor is turned on, the PWM control module 424 supplies power at a low voltage and increases the duty cycle, after a predetermined period, Power can be supplied at a higher voltage. In this way, the control method can be incorporated into existing PWM designs without the need for additional hardware.

  Furthermore, due to the flexibility of the PWM control method, various voltage ramp profiles are applied when increasing the voltage from the first voltage to the second voltage over a predetermined period. In one embodiment, the voltage may be increased linearly from a first voltage to a second voltage for a predetermined period. In another embodiment, power is supplied at a first voltage for the duration of a predetermined period and is immediately increased to a second voltage at the end of the predetermined period. Of course, other lamp shapes are possible, and embodiments of the invention are not limited to these examples.

  Referring now to FIG. 5, the steps of a method for powering an electric motor in a breast pump system are shown. The method is used to control the power supply that feeds the electric motor. In a first step S501, a signal to turn on the electric motor is received to start driving the vacuum pump. The signal may be received from a user, for example, or from control software that controls the operation of the breast pump system. Next, in step S502, the power supply starts feeding the motor with the first voltage.

  Next, in step S503, the first voltage is increased to the second voltage after a predetermined period. The predetermined period may be the time it takes for the motor to reach a desired operating speed. At that time, the resistance provided by the back EMF field is sufficient for a higher second voltage to be applied without causing power loss due to current spikes. As described above, the voltage may be gradually increased over the duration of the period so that the motor is smoothly accelerated. Alternatively, a step increase may be applied to increase the voltage immediately from the first voltage to the second voltage at the end of the period. A slow ramp is easily realized in a PWM system, while in non-PWM systems, step increments are more easily applied. This is because the power supply need only be able to supply two separate voltages, the first and second voltages. Finally, in step S504, after the period has elapsed, the power supply continues to supply power to the motor at the second voltage.

  Referring now to FIG. 6, a breast pump system is shown. In this embodiment, an operating unit 620 is provided for use in a breast pump system, such as the breast pump system shown in FIG. The operation unit 620 is the same as the operation unit of FIG. 2, and includes a vacuum pump 621, a DC electric motor 622, a power supply 623, and a power supply control module 624. Of course, in other embodiments, rather than providing a physically separate operating unit and milk collection unit, the components of the operating unit 620 and the collection unit may be incorporated into the breast pump body.

More specifically, in the present embodiment, the power supply control module 624 detects an input current supplied to the motor 622 by the power supply 623. The input current is referred to as the motor current I _M. The power supply control module 624 may directly detect the motor current or may receive a current measurement result from a separate current detection module (not shown).

  By monitoring the motor current, the power control module 624 determines whether a vacuum is already present in the breast pump funnel when the motor 622 is turned on. In normal operation, the vacuum should be released after each pumping cycle by opening a release valve (not shown in FIG. 6). However, if the vacuum is not released due to other reasons, for example, the release valve did not open or the inlet to the valve was clogged, the initial load on the pump 621 was turned on at the beginning of the next pumping cycle. Sometimes it is higher than the situation where the vacuum is released after the previous pumping cycle. In particular, if the vacuum is not released or only partially released, the load is higher because the pump 621 needs to operate against pre-existing vacuum conditions.

  In this embodiment, the motor current level at any point in time is used as an indicator of the vacuum pressure at a certain moment. A high motor current indicates that the motor 622 is drawing more current due to the higher load on the pump 621. When the motor current exceeds a predetermined threshold current indicating a pre-existing vacuum state, the power control module decelerates the electric motor. In the present embodiment, the power supply control module suspends power supply to the motor in order to turn off the motor. However, in other embodiments, the motor speed may be reduced without completely turning off the motor.

  By reducing the motor speed when the threshold current is exceeded, in an embodiment, it can be avoided that an excessively high vacuum is generated in the breast pump funnel even if the normal release mechanism fails. Such an embodiment allows a powerful pump 621 to be used. This powerful pump can reach the desired vacuum level more quickly without the risk of a high vacuum in the breast pump funnel even if the vacuum is not properly released at the end of each pumping cycle. In other embodiments, the current control process as described above is omitted if a low power pump is used that is not capable of producing a sufficiently high vacuum to cause, for example, discomfort or damage to the user.

Referring now to FIG. 7, a graph displaying motor current shape over time in the breast pump system of FIG. 6 is shown. Graph over three pumping cycle, displaying the motor current I _M with respect to time. The dashed line shows the measured motor current level during each pumping cycle when the current control method described above with reference to FIG. 6 is not used. A high current is observed at the beginning of each pumping cycle because the release valve has failed and the vacuum from the previous pumping cycle has not been released. In contrast, the solid line in FIG. 7 shows the measured motor current level when current control is applied. Again, after the first pumping cycle, the vacuum is not released because the release valve fails and does not function. However, since current control is applied, the pump is stopped when the threshold current is exceeded. By applying the current control method described above with reference to FIG. 6, the system quickly detects the presence of a high vacuum level in the breast pump funnel and decelerates the motor to prevent further increase in vacuum. be able to.

  Referring now to FIG. 8, method steps for use in a breast pump system as shown in FIG. 6 are shown. In the first step S801, the electric motor is turned on. Next, in step S802, the motor current is detected. Next, in step S803, the detected motor current is compared with a predetermined threshold current. The predetermined threshold current indicates a threshold vacuum level in the breast pump. If the threshold current is not exceeded, the process returns to step S802 and monitoring of the motor current is continued. However, if the threshold current is exceeded, the motor speed is reduced in step S804. For example, the motor speed is reduced by decreasing the drive voltage supplied to the motor or by disconnecting the motor from the power source. As described above, the method as shown in FIG. 8 can detect the presence of a high vacuum level in the breast pump funnel and decelerate the motor to prevent further increase in vacuum.

  In the embodiment described with reference to FIGS. 6, 7, and 8, the breast pump system is further configured to be low when the motor is turned on, as described above with reference to FIG. The electric motor is controlled by feeding with voltage and increasing the power to a high voltage after a predetermined period. However, in other embodiments, in order to prevent high vacuum, the current control process described in FIGS. 6, 7 and 8 may be used regardless of whether the motor control method of FIG. 5 is also used. Applicable to any conventional breast pump system.

  Referring now to FIG. 9, method steps for use in a breast pump system are shown. The method may be any of the breast pump systems described above with reference to FIGS. 1, 2, 4, and 6, or any conventional milking system that does not include the features of the system described above. It can also be implemented in a vessel system. To implement the method, a motor speed adjustment module is provided. In a first step S901, the electric motor is turned on, and in step S902, the motor is first driven at a first speed. Next, in step S903, after the load on the motor reaches a predetermined level, the motor speed is increased from the first speed to a second speed that is faster than the first speed. Next, in step S904, the system continues to drive the motor at the second speed.

  In step S903, various approaches are possible. In one embodiment, the breast pump system includes a load detection module that detects a load on the motor and provides feedback to the motor speed adjustment module. After reaching a predetermined load, the motor speed adjustment module increases the motor speed. Alternatively, rather than providing a footback, the system may wait for a predetermined period of time before driving the motor at a second, faster speed. The predetermined period is determined by measuring the time it takes for the load to reach a predetermined level under normal operating conditions during calibration of the breast pump system. Various ramp profiles are applied in increasing the motor speed. The speed is gradually increased from the first speed to the second speed as the load increases, or when the predetermined load is reached, it steps from the first speed to the second speed. May be increased by

  This method is advantageous in breast pump systems where the load on the motor is low at the beginning of each pumping cycle where there is no vacuum. As air is exhausted from the breast pump funnel to increase the vacuum level, the load on the motor is increased. In conventional systems, when constant power is supplied to the motor throughout the pumping cycle, the motor is initially supplied with a low load, so it moves at high speed at the beginning of the pumping cycle. The power is relatively high for low loads. This is uncomfortable for the user due to excessive noise caused by the initial high speed of the motor. In this embodiment, after the motor is turned on, the motor is intentionally driven at a low speed to reduce motor noise. The motor is driven at a first low speed by supplying a low voltage or by using PWM control and a reduced duty cycle.

  With reference to FIG. 10, a further aspect of the breast pump system is described. The features of this aspect of the breast pump system are any of the breast pump systems described above with reference to FIGS. 1, 2, 4 and 6, or any that do not include the features of the system described above. It can also be implemented with conventional breast pump systems.

  FIG. 10 shows a breast pump 1001. A breast pump 1001 is similar to the breast pump shown in FIG. 1 and is provided for use in a breast pump system as shown in FIG. The breast pump 1001 has a body 1002 in which a chamber 1003 is defined. The chamber 1003 is formed along a fluid passage 1004 between the funnel 1005 that receives the user's breast and the collection tank 1006. The chamber 1003 has a vacuum port 1007. The vacuum port 1007 is connected to a vacuum pump in an operation unit similar to the operation unit described in the above-described embodiment. Thus, the vacuum pump can provide a reduced pressure in the chamber 1003. The vacuum port 1007 is formed at the upper end of the chamber 1003.

  A membrane 1010 is received in the chamber 1003. Membrane 1010, also known as a diaphragm, is flexible. The membrane 1010 divides the chamber 1003 into a first space 1011 and a second space 1012. The first space 1011 is fluidly connected to the vacuum port 1007. Therefore, a reduced pressure is generated by the vacuum pump in the first space 1011. The second space 1012 is in fluid communication with a fluid passage 1004 between the breast receiving space of the funnel 1005 and the collection tank 1006. A one-way valve 1008 is disposed in the fluid passage 1004. The one-way valve 1008 eliminates the need to draw air from the collection container 1006 to create a reduced pressure, and eliminates the need to provide a sealed interface between the collection container and the body 1002.

  When a reduced pressure or vacuum is generated in the first space 1011, the membrane 1010 is deformed and drawn in the direction of the first space 1011. Therefore, the deformation of the membrane 1010 generates a reduced pressure in the second space 1012 of the chamber 1003. When the breast is received in the mouth of the funnel, a vacuum is formed in the funnel 1005. The reduced pressure acts on the user's breast and milk is squeezed out of the breast.

  The chamber 1003 has a base 1020, a side wall 1021, and an upper wall 1022. Side wall 1021 extends between base 1020 and upper wall 1022. The side wall 1021 extends in the circumferential direction of the chamber 1003. The chamber 1003 is formed of a lower chamber 1023 and an upper chamber 1024 that can be attached to each other. The lower chamber 1023 defines a base 1020 and a lower portion of the side wall 1021. Upper chamber 1024 defines an upper wall 1022 and an upper portion of sidewall 1021. The outer edge of the membrane 1010 can be attached between the lower chamber 1023 and the upper chamber 1024. Accordingly, the membrane 1010 is securely attached within the chamber 1003. This means that the membrane 1010 is in place in the chamber 1003.

  The vacuum port 1007 is connected to the chamber 1003 through the upper wall 1022, and the fluid passage 1004 is connected to the chamber 1003 through the base 1020. Base 1020, sidewall 1021, and top wall 1022 define the inner surface of chamber 1003.

  In this embodiment, the main body 1002 forming the chamber is formed from polypropylene. The flexible membrane 1010 is formed from silicone. Of course, however, the chamber 1003 and membrane 1010 may be formed from other suitable materials.

  The flexible membrane 1010 has a predetermined shape. In this configuration, the membrane 1010 has a substantially cup-shaped configuration in its neutral position, that is, when it is not deformed by the reduced pressure in the first space 1011. The membrane 1010 has a lower surface 1025 and an upper surface 1026. A lip 1027 extends from the free end of the membrane sidewall. However, it will be appreciated that the membrane may be formed to have a different shape. In this configuration, the lip 1027 is mounted between the lower chamber 1023 and the upper chamber 1024 to form a cavity 1003. In this embodiment, the membrane is inverted as the membrane 1010 deforms. Of course, however, in alternative embodiments, the membrane 1010 may not be inverted.

  Side wall 1021 has a textured surface. That is, at least a portion of the chamber surface has a textured surface. In this embodiment, the lower part of the side wall 1021 has a textured surface. The textured surface may extend over the entire lower surface of sidewall 102 or only a portion thereof. The part may include a part of the side wall that contacts the membrane 1010. The textured surface may cover all or part of the chamber surface. For example, a series of repeated patterns may extend around the chamber, each pattern having a surface texture.

  The textured surface is formed from a textured surface finish having an arithmetic average roughness (Ra) in the range of Ra 0.8 μm to Ra 3.2 μm. A perfectly smooth or high gloss finish (± Ra 0.05 μm) is achieved when the flexible membrane 1010 is deformed in the chamber 1003 by the membrane 1010 and the chamber surface sticking together. It has been found that squeak noise is caused.

  It has also been found that a surface having a roughness higher than, for example, Ra 3.2 μm results in high wear of the membrane 1010 as the membrane 1010 moves over the surface. Thus, a surface finish in the range of Ra 0.8 μm to Ra 3.2 μm minimizes noise caused by the deflection of the membrane 1010 relative to the surface while minimizing membrane wear by the surface.

  In one embodiment, a surface having a textured surface has an arithmetic average roughness (Ra) of Ra 1.6 μm. It has been found that a surface with this value of arithmetic mean roughness minimizes membrane wear while minimizing noise during use of the breast pump.

  The textured surface is formed by in-mold texturing. That is, the textured surface is formed by adding, for example, a texture that is an electric discharge machining texture to a tool that forms the main body 1002. Alternatively, the textured surface is formed after the body is manufactured, for example by sandblasting. Other methods of forming a textured surface may be used.

  Membrane 1010 is received in chamber 1003 when the breast pump is assembled. The lower surface 1025 of the membrane 1010 is arranged close to the surface of the chamber 1003, for example, a lower part of the side wall 1021, but slightly spaced. At this time, the membrane 1010 is in its neutral position, that is, in an undeformed position. Alternatively, the lower surface 1025 of the membrane 1010 may be placed in contact with the surface of the chamber 1003 in a neutral position.

  When the milking machine 1001 is operated, the membrane 1010 is deformed by bringing about a reduced pressure in the first space 1011. When the membrane 1010 starts to deform, the membrane 1010 is in contact with the surface of the chamber 1003 or is in contact with the surface of the chamber 1003 from the beginning. Of course, a portion of the surface of the chamber 1003 that contacts the membrane 1010 has a textured surface.

  When the membrane 1010 is further deformed, the lower surface 1025 of the membrane 1010 moves away from the surface of the side wall 1021 and / or the side wall 1021 as the membrane 1010 is deformed by the reduced pressure in the first space 1011 of the chamber 1003. Drawn on the surface. Similarly, of course, the lower surface 1025 of the membrane 1010 may contact the surface of the side wall 1021 as the membrane 1010 returns to its neutral position by release of reduced pressure in the first space 1011 of the chamber 1003 and / or , Move on the surface of the side wall 1021.

  Since the membrane 1010 contacts or moves away from the textured surface, the contact area formed between the membrane 1010 and the surface of the chamber 1003 is minimized. Therefore, noise caused by movement of the membrane 1010 and the surface of the chamber 1003 relative to each other is minimized. For example, since the surface area is reduced, there is less sticking between the membrane 1010 and the surface of the chamber 1003.

  One advantage of having a portion of the chamber with a textured surface is that the reduction in the surface area of contact between the membrane and the chamber surface minimizes the friction caused between the membrane and the chamber. is there. Therefore, it becomes easier to move the membrane within the chamber. This means that less energy is required to deform the membrane in the chamber and return the membrane to its neutral position.

  In the above embodiment, the textured surface is formed in the lower part of the side wall between the base and the membrane, but it should be understood that the textured surface is alternatively the membrane and top wall. It may be formed on the upper part of the side wall between the two. This configuration minimizes any noise caused by contact between the membrane and the top of the sidewall.

  In the above embodiment, the textured surface is formed on the side wall of the chamber, but of course the textured surface is in contact with the membrane while the membrane is deformed, or the membrane May be formed on any surface of the body that moves away from it. In particular, the base and / or the top wall may have a textured surface.

  In the above embodiments, a textured surface finish is formed on the surface of the chamber, but it should be understood that the textured surface may alternatively be formed on the surface of the membrane. This has the same effect of reducing the contact area between the membrane surface and the chamber surface. The textured surface may be formed on all or part of the lower surface of the membrane and / or may be formed on all or part of the upper surface of the membrane.

  Of course, although the embodiments are described and illustrated as including particular elements, which may be referred to as components, modules or units, the illustrated structure is merely exemplary. The illustrated elements may be physically separate hardware components or may be incorporated into a single module that performs the functions of the individual modules shown in any embodiment. For example, in FIG. 2, the description of the voltage detection module 224 and the motor interruption module 225 does not imply that these modules are physically separate. In one embodiment, both modules may be embodied in a single chip that includes an ADC as the voltage detection module 224 and additional hardware that performs the functions of the motor interruption module 225. In some embodiments, the function of one or more components may be performed by a processor executing software instructions.

  In the above embodiment, the pump unit is provided with separate means for generating a reduced pressure in the vacuum path and releasing the reduced pressure in the vacuum path, but of course these means may be integrated. . In another embodiment, the pump unit includes a piston that is slidably received within a piston chamber or cylinder. The piston functions as a reciprocating element. The piston forms a fluid seal within the chamber. The piston chamber forms part of the vacuum path. The piston is manipulated to repetitively move, for example, by a crankshaft and a motor. As the piston is retracted along the piston chamber, the movement of the piston acts to create a vacuum in the vacuum path. Thus, a vacuum is generated in the user's breast. When the piston moves in the opposite direction in its return process, the vacuum in the chamber is released. However, if, for example, the piston stops or the motor fails, the piston will not release the vacuum in the vacuum path. That is, the pump unit cannot release the reduced pressure in the vacuum path. In this case, the decompression in the vacuum path is released while being controlled by the leakage aperture provided in the vacuum path.

  In the above embodiment, of course, a vacuum path is formed between the piston and the user's breast when the breast pump system is assembled and the user's breast is received in the funnel. The pump unit may be disposed in the operation unit or may be accommodated in the breast pump.

  In another embodiment, the pump unit is formed by a membrane and means for mechanically deforming the membrane. The membrane functions as a repetitive element. For example, a rod that can be moved repeatedly by an electric motor is attached to the deformable membrane. In this configuration, deformation of the membrane from the neutral state of the membrane creates a reduced pressure in the vacuum path. The membrane then returns to its neutral state, releasing the vacuum in the vacuum path. In this embodiment, of course, a vacuum path is formed between the membrane and the user's breast once the breast pump system is assembled and the user's breast is received in the funnel. However, if the membrane does not return to its neutral state, for example due to a failure of the electric motor, the membrane does not release the vacuum in the vacuum path. That is, the pump unit cannot release the reduced pressure in the vacuum path. In this case, the decompression in the vacuum path is released while being controlled by the leakage aperture provided in the vacuum path. This membrane may be the membrane described in the above embodiment, or may be another membrane arranged independently.

  In the above two embodiments, of course, no pressure relief valve is required since the vacuum is released by returning the valve or membrane to its neutral position.

  Of course, the term “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality. A single processor may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measured cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope of the claims.

  In this application, the claims are made for specific feature combinations, but it is to be understood that the scope of the present disclosure is any novel or explicit disclosure herein. Features or any combination of novel features, or the same technical problem as the technical problem that the present invention alleviates, whether or not it relates to the same invention currently claimed in any claim Regardless of whether any or all of them are reduced, the generalization of the feature is also included. Applicant notes here that a new claim may be made for the feature and / or combination of features during the examination procedure of this application or any further application derived from it. .

Claims (15)

A pump unit;
An actuator for driving the pump unit;
A power source for supplying power to the actuator;
When the pump unit is turned on, the actuator is driven at a first speed, and after the load applied to the actuator reaches a predetermined level, the actuator is moved to a second speed higher than the first speed. An actuator speed adjustment module that continues to drive at speed,
Including a breast pump system.   The power supply uses pulse width modulation to power the actuator, supplies a first voltage by powering at a first duty cycle, and a second duty cycle higher than the first duty cycle The breast pump system according to claim 1, wherein the second voltage is supplied by supplying power at.   The breast pump system according to claim 1 or 2, wherein the power source gradually increases the first voltage to the second voltage during a predetermined period.   A power control module for detecting an input current supplied to the actuator and reducing the speed of the actuator in response to the detected input current exceeding a threshold current level indicating a threshold vacuum level in the breast pump The breast pump system according to any one of claims 1 to 3, further comprising:   The breast pump system according to claim 4, wherein the power control module temporarily interrupts power supply to the actuator to reduce the speed of the actuator. The pump unit further includes
A vacuum pump,
A valve for releasing the vacuum generated by the vacuum pump;
Including
6. A breast pump system according to claim 4 or 5, wherein in response to the detected input current exceeding the threshold current level, the power control module further indicates a failure of the valve.   The power source powers the actuator using pulse width modulation according to a duty cycle, and the power control module powers the actuator by setting the duty cycle of the pulse width modulation to substantially zero. The breast pump system according to any one of claims 4 to 6, wherein the system is temporarily suspended.   When the pump unit is turned on, a first voltage is supplied to the actuator. After a predetermined period after the pump unit is turned on, the actuator is supplied with a second voltage higher than the first voltage. The breast pump system according to any one of claims 1 to 7, further comprising a power supply control module that controls the power supply so as to supply the voltage.   The breast pump according to claim 8, wherein the predetermined period is a time taken for the pressure difference generated by the pump unit to reach a predetermined level. A chamber;
A membrane receivable in the chamber so as to divide the chamber into a first space and a second space;
Further comprising a breast pump having
The membrane is deformable in the chamber in response to a reduced pressure in the first space to provide a reduced pressure in the second space;
The surface of the chamber that can contact the membrane and / or the surface of the membrane that can contact the chamber is in contact with the chamber, moves along the chamber, or moves away from the chamber. 10. A breast pump system as claimed in any one of the preceding claims, having a textured surface finish so that the noise level produced during movement is minimized.   The chamber includes a sidewall on which the membrane is placed before and / or during deformation, the surface having the textured surface finish being accessible to the sidewall and / or the sidewall The breast pump system of claim 10, formed by a portion of the membrane.   12. The breast pump system of claim 10, wherein the surface has a textured surface finish having an arithmetic average roughness (Ra) of Ra 0.4 [mu] m to Ra 3.2 [mu] m. A method for use in a breast pump system comprising: a pump unit; an actuator for driving the pump unit; and a power source for powering the actuator,
When the pump unit is turned on, driving the actuator at a first speed;
Continuing to drive the actuator at a second speed higher than the first speed after a load on the actuator reaches a predetermined level;
Including a method. Detecting an input current supplied to the actuator;
Reducing the speed of the actuator in response to the detected input current exceeding a threshold current level indicative of a threshold vacuum level in the breast pump;
14. The method of claim 13, further comprising: Powering by supplying a first voltage to the actuator when the pump unit is turned on;
Supplying a second voltage higher than the first voltage to the actuator after a predetermined period after the pump unit is turned on;
15. The method according to claim 13 or 14, further comprising: